Carrier bags having handles with snap-fastener locking means



Sept. 15, 1970 NN 3,528,471

CARRIER BAGS HAVING HANDLES WITH SNAP-FASTENER LOCKING MEANS Filed April25, 1959 INVENTOR Emi-l Harfmann rZAw LwQ ATTORNEYS A I United StatesPatent O 3,528,471 CARRIER BAGS HAVING HANDLES WITH SNAP-FASTENERLOCKING MEANS Emil Hartmann, Zurich, Switzerland, assignor to CTPgldliistries Inc., Brooklyn, N.Y., a corporation of New Filed Apr. 23,1969, Ser. No. 818,728 Claims priority, application Switzerland, Apr.25, 1968, 6,154/ 68 Int. Cl. B65d 33/24 US. Cl. 150-3 4 Claims ABSTRACTOF THE DISCLOSURE Snap-fastener type locking means for handles of thetype affixed to the mouth of a carrier bag. Stud and recess elements areprovided on the opposed handle portions. The stud portion extendsthrough the recess on the opposite handle part and is provided with anoverhanging portion which is resilient and deformable and capable ofbeing latched behind a protruding part in the recess on the oppositemember. As a result, the two members are locked securely together andquite strongly oppose separation in response to forces tending toseparate the bag walls, whereas the handle members are quite readilyseparable when the two hand-grip portions are prized apart.

BACKGROUND OF THE INVENTION Thermoplastic carrier bags which areprovided with a pair of handle members at the opposed bag walls adjacentthe rnouth of the bag and with means for snap fastening together the twohandle members are now wellknown in the art. Generally, the two handlemembers each comprise a longitudinal sealing bar and acentrally-disposed looped gripping portion which is integral with thesealing bar.

The sealing strip and/ or the looped hand-grip portion may carry one ormore snap fastener elements generally comprising a protruding stud onone part and a mating recess on the other. Each handle is affixed to thebag wall at its mouth by heat sealing the longitudinal sealing strip tothe open edge of the bag. Such bags may be frequently re-used and arehighly convenient to the user because the bag mouth may be closed toguard against loss of the bag contents and entry of dirt, rain, etc.

One of the problems connected with the use of plastic carrier bags ofthis general type is that, although the snap fastener means must be ofsuch a type as to readily per-mit opening of the bag by prizing apartthe two handle members, the handles should not be readily separable asthe result of forces exerted on the bag walls as may result from thecarrying of a load of goods in the bag. Thus, it is quite desirable thatthe locking means on the two handle portions be able to resist quitestrongly any tendency to separate the handle portions resulting fromopposed lateral forces acting on the bag walls which are connected tothe aforesaid respective longitudinal sealing strips.

SUMMARY OF THE INVENTION The invention comprises a snap-fastener typelocking means for handles for carrier bags which is readily openablewhen the two handle portions are prized apart at the location of thelooped gripping handles, but strongly resist separation when an equalamount of force is applied on the handles through the bag walls.Consequently, the bag can readily be opened by the user, but will notreadily be inadvertently opened as the result of stresses from a load inthe bag.

The aforesaid improved resultsare obtained by providing a stud andrecess combination in which the stud on 3,528,471 Patented Sept. 15,1970 one of the handle parts is provided with an overhanging portionwhich extends into and over a protrusion within the recess of theopposed handle part. The overhanging portion and also the protrusion arein the bottom por tion of the stud-recess combination, i.e. toward thebag walls which are secured to and depend from the longitudinal sealingstrip. At the topside of the stud-recess combination, i.e. the side moreclosely adjacent the looped gripping handle, the stud and recess areboth fully curved with no projections nor engaging protrusions. As aresult, any separating forces exerted on the two handle parts fromabove, i.e. forces tending to separate the looped gripping handles, willquite readily result in releasing the snap fasteners; however, forcesexerted which tend to separate the longitudinal sealing strips frombelow cause the above-mentioned protrusion to become quite securelyengaged within and behind the overhanging portion of the stud so thatthere is a strong tendency to resist separation of the stud and recess.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view of a typical carrierbag having thermoplastic bag walls and engageable handle portions whichare secured to the bag walls at the mouth thereof;

FIG. 2 is a detailed view of a single one of the stud and recesscombinations shown in FIG. 1;

FIG. 3 is a cross-sectional view taken along the section line 33 of FIG.1;

FIG. 4 is a cross-sectional view of a stud and recess combinationaccording to an alternative embodiment of the invention; and

FIG. 5 is a perspective view of still another embodiment of theinvention.

DETAILED DESCRIPTION OF THE INVENTION FIG. 1 illustrates a plasticcarrier bag having opposed front and rear bag walls which are formed ofa thin-film thermoplastic material. Inside the bag mouth are secured apair of handle members 12 and 13 each of which comprises a longitudinalsealing strip 14, 15, and a centrally disposed looped hand-grip portion16, 17. Preferably the handle members 12 and 13 are heat sealed to thebag walls along the respective sealing strips 14 and 15. When the bagmouth is to be closed, the two handle portions 12 and 13 are broughttogether and are releasably secured together by means of one or morestud-recess combinations 18 which may be located either along thelongitudinal sealing strip or in the looped hand-grip portion, but whichare preferably located adjacent the region where each looped hand-gripportion joins the longitudinal sealing strip as shown in FIG. 1.

The view of FIG. 2 illustrates in greater detail the combination of astud and recess for releasably securing two handle portions 12 and 13together, and FIG. 3 is a crosssectional view of the stud and recesscombination of FIG. 2.

One ofthe handle portions 13 is shown as being provided with a stud 19which is of generally circular crosssection as shown in FIG. 2. The studis hollowed out at 20 as shown in FIG. 3. The hollowed-out portion hasgenerally the configuration shown by the solid lines in FIG. 2designated as 21, 22, 23, and 24. The clearance which is provided byhollowing out the stud along the solid lines 22, 23, and 24 providesclearance for the stud over the protuberance 25 which is provided withinthe recess defined in the opposed handle portion 12. Preferably theprotuberance is smoothly curved downwardly toward the entranceway of therecess, but is also provided with an abrupt vertical wall 28 behindwhich the overhanging lip 27 can readily be engaged. Since the handleportions are principally formed of a rather flexible, deformable plasticmaterial such as polyethylene, it can be seen that when the stud 19 isinserted into the corresponding recess 26 defined in member 12, therewill be clearance over the protuberance 25, and it will be necessaryonly to exert sufficient force to cause the lower lip 27 of stud 19 topass over the protuberance 25 and be engaged against the back edgethereof, thereby effectively locking the stud in place in the recess.

It can be seen from FIG. 3 that any force applied along the direction ofthe arrows A to separate the two handle portions 12 and 13 will readilyresult in slippage of the surface 29 of the recess 26 over the smoothlycontoured upper surface 30 of stud 19, and once these surfaces 29 and 30are free of each other, continued separation of the handle portions 12and 13 quite readily causes the protuberance 25 to slip out from behindthe lower edge 27 of the overhanging lip so that the two handle membersare then readily disengaged from each other. On the other hand, if thesetwo members are sought to be separated by lateral forces applied theretoin the direction of the arrows B, then it is found that there is greatresistance to such separation since the protuberance 25 is then quitefirmly locked behind the overhanging lip 27 of stud 19, and it is foundthat several times as much force must then be applied to separate thehandle members 12 and 13 as is required when forces are applied in thedirections of the arrows A.

FIG. 4 illustrates an alternative embodiment of the invention in whichthe stud 31 is provided with an overhanging lip portion 32 as before butthe stud is not provided with a generally hollowed-out portion over itsmajor cross-section. Instead, only a portion of the stud is hollowed outalong its bottom portion at 33 so as to provide clearance for theprotuberance 34. Otherwise, the stud and recess combination of FIG. 4operates in much the same way as that of FIGS. 2 and 3.

In the embodiment of FIG. 5, the stud is hollowed out, with thehollowed-out portion being generally circular, but leaving anoverhanging lip portion 35. The recess is again provided with aprotuberance 36 which can engage with the lip 35 to restrain separationof the two handle portions by lateral forces applied along the bottomsof the respective handle members. In the embodiment of FIG. 5, theprotuberance is illustrated as being generally located within therecess, and more closely toward the opposed handle portion than is thecase in the embodiment of FIGS. 2 and 3, and the embodiment of FIG. 4.

Although the stud and recess of the embodiments disclosed herein areshown to have a generally cylindrical configuration, this is notessential, and they may very well have different configurations such asan oblong or irregular cross-section.

What I claim is:

1. In a carrier bag of the type having opposed bag walls and a pair ofhandle members formed of a flexible deformablematerial each secured to abag wall at the mouth of the bag and with each handle member having aportion which is sealed to a bag wall and having also an integralhand-grip portion, the improvement which comprises:

snap-fastener locking means for said handle members comprising a stud onone handle frictionally and releasably engaging within a recess formedin the other handle member,

said stud being of generally cylindrical configuration and projectinglaterally outwardly of said one handle member,

said recess having a protuberance therein in the circumferential portionthereof which is most closely adjacent the location at which a bag sidewall is secured to the relevant handle member,

said stud having a part of its cylindrical body portion removed from itspoint of juncture with the respective handle member axially therealongto a point near its remote end to thereby provide an overhanging lip ata said remote end which passes over and effectively locks behind saidprotuberance when said stud is fully inserted into said recess,

said body portion which is removed providing clearance for saidprotuberance,

whereby lateral forces on said bag walls in a direction tending toseparate said handle members are strongly resisted by the locking effectof said protuberance and overhanging lip whereas exerted on thehand-grip portions of said handle members readily result in separationof said handle members.

2. The carrier bag of claim 1 in which both said stud and said recessare of generally circular cross-section.

3. The carrier bag of claim 1 in which said protuberance is smoothlycurved axially along said recess so as to protrude with increasing depthinto said recess in the direction of insertion of saidstud.

4. The carrier bag of claim 3 in which the curved surface of saidprotuberance terminates abruptly in a surface which is substantiallytransverse to the axis of said recess to provide thereby a surfaceagainst which said overhanging lip can abut when said stud is fullyinserted into said recess.

References Cited UNITED STATES PATENTS DAVID M. BOCKENEK, PrimaryExaminer U.S. Cl. X.R. --12; 22954

